import copy
a=[1,2,3]
b=a
c=copy.copy(a)

print("a的id：",id(a))
print("b的id：",id(b))
print("c的id：",id(c))

print("a==b",a==b)
print("a is b",a is b)
print("a==c",a==c)
print("a is c",a is c)
